<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>网页计算器</title>
</head>
<body>
    <form action="/servlet/calculator">
        <input name="first" value=""/>
        <select>
            <option name="operator">+</option>
            <option name="operator">-</option>
            <option name="operator">*</option>
            <option name="operator">/</option>
        </select>
        <input name="second" value=""/>
        <input type="submit" value="=">
        <input value="" disabled="disabled">
    </form>
<!--</body>-->
</html>